The present invention relates generally to the treatment of termite colonies with a termiticide, and, in particular, to a subterranean termite bait station for attracting termites and a method utilizing the subterranean termite bait station in the treatment of a termite colony with a termiticide that is non-repellent to termites and, preferably, lethal to termites through ingestion, contact and/or transferal.
Termites do more property damage in the United States than hurricanes, earthquakes and vandalism combined. In order to control termites with a toxicant (hereinafter xe2x80x9ctermiticidexe2x80x9d), termites must come in contact with the termiticide. Termites ingress and egress a food source through underground and above ground tunnel tubes which extend between a colony nest and the food source, e.g. a building. These tunnel tubes are climate controlled and impervious to termiticides sprayed on the soil and, for as long as the termites remain sealed within their tunnel tubes, the termites are protected from contact with the termiticides sprayed on the soil.
For decades, one method for controlling termites has included the saturation of the soil in a zone under and surrounding a building. To get the termiticide within the termite tunnel tubes, a trench is dug around the building. This breaks the walls of the termite tunnel tubes passing through the zone. The soil from the trench is saturated with termiticide and the trench is filled with this termiticide treated soil. As the termites repair their fractured tunnel tubes, the termites come into contact with the termiticide treated soil and the termiticide is thereby introduced into the colony.
Other methods for controlling termites involve breaking into visible, above ground termite tunnel tubes and injecting a termiticide into the tunnel tubes with a syringe or breaking into visible, above ground termite tunnel tubes and placing a device containing termiticide in the pathways of the termite tunnel tubes. A major problem encountered, when using these methods of termite control, is locating the termite tunnel tubes, which for the most part are hidden behind stucco facings, in wall voids, etc.
In addition to the above methods, there are numerous methods in commercial use for treating termite colonies with termiticides which use termite bait stations, but typically, these methods for treating termite colonies with termiticides use bait stations, such as the termite bait station of U.S. Pat. No. 5,937,571, issued Aug. 17, 1999, which incorporate toxic baits within the termite bait stations, such as slow acting toxicants and/or growth inhibitors. In another method for treating termite colonies with termiticides, the termites are enticed to form a pheromone trail to a bait station to feed on nontoxic sticks of cellulose, such as wood or cardboard. After the members of the termite colony are feeding at the bait station, the pest control technician removes the nontoxic bait and replaces the nontoxic bait with a toxic bait or leaves the nontoxic bait in place and places a toxic bait adjacent the nontoxic bait. U.S. Pat. No. 6,079,150, issued Jun. 27, 2000, discloses such a method of treating termite colonies with termiticides.
When termites ingest termiticides and die shortly after feeding at a bait station, other termites in the colony associate the death of their companions with the new food source (the bait in the bait station) and cease to feed at the bait station. In an attempt to minimize this problem, a slow acting termiticide may be used or toxic baits may be substituted or placed adjacent nontoxic baits after the termites have been feeding at the bait station for a period of time. However, slow acting toxicants can prolong the treatment period required to control the population of a termite colony and any disturbance of the bait in the bait station, through the replacement of the nontoxic bait with a toxic bait or the introduction of a separate toxic bait adjacent the nontoxic bait, may cause the termites to stop feeding at the bait station. Even with the use of slow acting toxicants, most bait stations must be opened and the bait disturbed or removed to determine if there is any termite activity within the bait station.
Thus, there has been a need to provide a method for treating termite colonies which does not use a toxic bait in the bait station container; permits the detection of termite activity within the bait station container with little or no disturbance of the bait; permits the treatment of the termites feeding at the bait station with a termiticide without contaminating the bait within the bait station with the termiticide; and, preferably, utilizes a termiticide which is non-repellent to termites and lethal to termites through ingestion, contact and/or transferal.
The method and the bait station of the present invention accomplish all of the goals listed immediately above. Since most termite tunnel tubes enter a building or structure (hereinafter xe2x80x9cbuildingxe2x80x9d) through cracks in the foundation, expansion joints, and/or control cracks in the floor slab of the building, all of which are generally relatively inaccessible, the method of the present invention utilizes a bait station containing a nontoxic bait to lure the termites to an accessible location outside of the building where termiticide can be introduced into the termites tunnel tubes leading from the colony to the bait station.
The bait station of the present invention is a container for holding nontoxic bait which is adapted to be located on or beneath ground surface adjacent a building to attract termites to the bait station. The container has one or more openings in its bottom wall through which termites may have subterranean ingress and egress to and from the interior of the container to feed on the nontoxic bait e.g. a cellulose bait such as wood or paperboard, within the container. The container also has one or more openings in an upper wall of the container which, preferably, are each centered over an opening in the bottom wall of the container, for monitoring termite activity within the container and for passing a termiticide injection tube or syringe down through both the container and the opening in the bottom wall of the container to introduce a termiticide directly into the soil beneath the container and the one or more termite tunnel tubes leading into the container through the opening(s) in the bottom wall of the container with little or no disturbance of the termites feeding within the container and without introducing the termiticide into the container where the termiticide would contaminate the nontoxic bait. Preferably, the opening(s) in the upper wall of the container are each provided with a flap for sealing, opening and resealing the opening(s) in the upper wall of the container to permit the upper wall of the bait station to be closed except when termite activity within the station is being monitored or termiticide is being introduced into the termite tunnel tube(s) leading into the bait station. Preferably, the bait station includes a metal component, such as but not limited to a foil closure flap for the openings in the upper wall of the container or a foil label, so that, when the bait station is buried, the location of the termite station may be detected with a metal detector.
In the preferred embodiment of the method of the present invention, the termiticide utilized to treat the termite colony is a non-repellant termiticide that is lethal to termites through ingestion, contact and/or transferal. With this type of termiticide, it is not necessary for the termites to feed on toxic bait. By introducing the termiticide into the soil beneath the bait station container, the termiticide can be introduced directly into the tunnel tubes beneath the bait station through which the termites travel between the colony nest and the bait station thereby leaving the bait station free of toxicants and safe to use where children or pets might gain access to the bait station. When termites pass through a treated tunnel tube, through contact with the termiticide within the tunnel tube, at least a few molecules of the toxicant within the tunnel tube will adhere to each of the termites. These termites will then carry the toxicant back to the colony nest. Since termites are social insects, other termites will groom the contaminated termites and, in turn, be groomed by other termites to spread the contamination throughout the colony. In this way, the entire colony including the reproductive(s) of the termite colony and the workers feeding upon the building, are destroyed, thereby, eliminating the need to drill holes through the foundation or walls of the building to treat the termites.